A vertical transportation device that uses a gear pinion on the car engaging a fixed vertical rack mounted on the structure to climb or descend, commonly used as a construction hoist and in industrial or outdoor applications.
Full Definition
A rack-and-pinion lift (also called a gear-rack lift or mast climber when used for construction) uses one or more motor-driven pinions that mesh with a toothed rack fixed to a mast or structural guide. The system can operate without a traditional hoistway, making it suitable for external building faces, industrial towers, wind turbines, offshore platforms, and construction sites. Drive motors are typically mounted on the car, eliminating the need for machine rooms or ropes. Operating speeds range from 0.3 m/s (construction hoists) to 1.0 m/s or higher (permanent industrial installations). Safety devices include: rack-engaging safety gear that clamps the rack on overspeed, anti-fall pawl, and overload sensor. EN 12159 governs building construction hoists for persons and materials. Permanent rack-and-pinion lifts for persons in buildings are covered by EN 81-31 (accessible goods-only) or the general EN 81-20 principles adapted by the notified body. Maintenance is more intensive than rope lifts due to rack, pinion and gearbox wear.
